If you want to accelerate your fitness, focus, fat loss, enhance your health or increase longevity, biohacking is the secret tool you’ve been looking for. The term has been known since 1988, but became popular around 2005, when famous biohackers like Dave Asprey, Tim Ferriss and Ben Greenfield, showed us all how to make dramatic changes to health and wellbeing with various lifestyle, dietary, supplemental and technology-driven protocols. In this blog series, you’ll learn all about the benefits of biohacking, the best biohacking practices to start right now, and how to become a biohacker yourself.

What Is Biohacking?

Biohacking, also known as ‘human enhancement’ or ‘do-it-yourself biology’, is a method of changing your body’s chemistry and physiology through self-experimentation, with the intention to improve your health, vitality and energy. If you ask any health expert ‘what is biohacking?’, their answer could include any number of categories, including lifestyle, nutrition, supplementation, wearable technology, and even implant technology. The purpose is to ‘hack’ or make effective, fast and noticeable improvements to your body and mind, often with techniques you may have never even heard of before.

Biohacking now has a growing community of participants worldwide, with the biohacking market set to reach 63 billion dollars by 2028. [1] This however, definitely doesn’t mean that biohacking has to be expensive. Many of the biggest benefits of biohacking are actually free. Today, we’re starting with one of the most popular, affordable and best biohacks; cold exposure.

What Is Cold Exposure Therapy?

Cold immersion, cold exposure, and thermogenesis are all terms to describe cold exposure therapy, which is essentially the practice of getting very cold, and reaping the benefits. Exposing the body to low temperatures can have significant benefits for metabolism, fat loss, energy levels, mental health, mood, energy and vitality, as well as exercise performance and recovery. [2] Research even shows that cold showers could be an effective treatment for the symptoms of depression, [3] as improvements in mood can be found for hours and days following even a short bout of cold exposure. [4]

How To Practice Cold Exposure

Before we dive into the benefits of cold exposure, and how to practice cold immersion to improve your health, it’s important to note that you should always practice safely. If you have an underlying medical condition or are at all unsure of whether this is safe for you, please speak to your healthcare provider.

There are several ways to expose your body to low temperatures to get the benefits of thermogenesis, including:

• Cold water immersion tub or ice bath: Most scientific studies have been performed on participants in cold tubs, so if you’re looking for hard evidence on the benefits of cold exposure, most of the research is on this type of biohack. Submerging your body up to the neck in cold water or an ice bath is a popular and arguably the most effective way to reap the benefits of cold exposure, such as increases in metabolism, fat loss and focus.

• Cold showers: There are less studies conducted on cold showers, yet this is probably the protocol most people will choose, as it’s the most affordable, quick and convenient. Cold showers can give you the benefits of cold exposure too, such as improvements in mood, energy, increased fat burning and cognitive function.

• Spending time outside in cold weather: The body loses heat a lot quicker in cold water than cold air [5], but if you’re able to spend time outside (we’ll cover exactly how much time later in the article) in cold weather, you’ll still get great benefits from cold exposure.

• Cryotherapy chambers: A whole-body cryotherapy chamber exposes the body to very low temperatures for a short amount of time. The main benefits of cryotherapy chambers are decreasing inflammation, reducing pain, remedying skin conditions, and even treating cancer, ligament pain, nerve damage and mood disorders. A cryotherapy chamber is expensive however, and not something you’re likely to come across every day.

• Ice vests and cooling vests: Cooling vests can be used to increase physical performance by lowering and stabilising body temperature, and athletes often use these to help enhance oxygen delivery to muscles. To truly lower your body temperature to prevent over-heating or to improve your athletic performance however, studies show that cooling three specific parts of the body can have a more powerful impact on lowering body temperature than trying to cool the neck or head. The most effective way to quickly lower core body temperature is to focus on cooling down the upper parts of the face, palms of the hands and soles of the feet. These areas of the body contain ‘glaborus skin’, which contain specialised vascular structures that facilitate heat loss. [6] If you want to ensure you’re fully immersing your body in cold temperatures then, it’s also important to ensure the hands and feet are submerged or at least getting cold too.

The Benefits Of Cold Exposure

Your physical and mental health can greatly benefit from cold immersion; here are five key benefits of cold exposure and thermogenesis;

1. Benefits of cold exposure for metabolism and fat loss

Immersing your body in cold water can help reduce the ‘white fat’ linked to obesity, and stimulate more so-called ‘brown fat’. Brown fat is a type of fat that babies and young children have in large amounts, specifically around the back, neck, clavicles, and around the shoulders. This type of fat is full of mitochondria (cell organelles that generate ‘ATP’, the currency the body uses for energy. The healthier and more abundant your mitochondria, essentially the more energetic, young, resilient and healthy you feel), and is used in energy expenditure and thermogenesis (heat production in the body). As we age, we gradually lose brown fat, and much of it is replaced with white fat. As you’ll probably know, excessive amounts of white fat are associated with obesity, type 2 diabetes, cardiovascular disease, and increased risk of many other diseases. [7] Research shows that cold immersion helps recruit more brown fat cells, and increase brown fat mass, leading to increased mitochondrial health, more energy, and a stronger metabolism. Studies also show that repeat cold water immersion can significantly increase insulin sensitivity, and decrease insulin concentrations, effectively reducing the risk of type 2 diabetes. [8] Some of the benefits of cold immersion and cold exposure occur due to the reaction of shivering, which encourages the release of succinate; a metabolite that acts on brown fat to increase thermogenesis and overall fat burning. [9] If your main focus is on improving your metabolism and burning fat, make sure you end your shower on cold, or allow your body to heat up naturally by itself after your cold immersion, otherwise the metabolism-boosting effects may be blunted.

2. Cold exposure for mental health and focus

Being immersed in cold water triggers the release of adrenaline, noradrenaline and dopamine, all of which have remarkable effects on mental state. One of the biggest benefits of cold exposure is its ability to help us deal with stress in the real world. Cold immersion is a ‘hormetic stressor’, or a ‘beneficial stress’, which when practiced in a controlled environment, can help us become more resilient. This is also known as ‘eustress’, which is thought of as a ‘positive form of stress, having a beneficial effect on health, motivation, performance and wellbeing’. [10] The release of adrenaline when we’re in a cold shower or ice bath greatly enhances energy levels and mental focus, and reduces pain; noradrenaline encourages the breakdown of fat stores, and also enhances energy production. These neurotransmitters are also released when we experience stress, so by being able to practice mimicking a stressful situation and staying calm and clear throughout, we help train the body and brain to become more resilient and able to handle real-life stressful situations. Studies even show that immersion in cold water can raise levels of noradrenaline by 530%. Your mental cold exposure training could include taking a cold shower whilst focusing on your breathing, thinking through maths problems, or trying to solve problems in your mind, to help encourage your mind to stay clear and focused even when you’re under stress.

Another specific benefit of cold water immersion is the impact it has on our dopamine levels. As you may have read in our previous blogs on using dopamine to create healthy habits that last, and surprising ways to boost your motivation, dopamine is a key neurotransmitter that increases alertness, motivation, drive, the desire to move, and also has great benefits for mood levels. Low levels of dopamine are associated with depression, and so using cold exposure to increase dopamine can work as an effective therapeutic tool for depression. [12] Raising your dopamine levels is absolutely essential if you want to boost your motivation, so if you’re feeling sluggish in the morning, have a demanding day ahead of you, or need to focus ahead of a stressful meeting, it’s worth noting that cold exposure can raise levels of dopamine by 250%.

3. Cold Exposure For Immune Health

Does cold immersion boost the immune system? Well, scientific studies have found that taking regular cold showers raises the number of white blood cells in the body, increasing protection against disease. Researchers believe this is related to an increase in metabolism, which also stimulates the immune response. [13] A clinical trial in the Netherlands found that cold showers led to a 29% reduction in people missing work due to sickness, and further studies even link cold showers to improved cancer survival rates. [14] [15] Wim Hof is one of the most prominent figures in the world of ice baths and cold water exposure, and he has been able to show how breathing practices, mind set and cold exposure can all contribute to fighting off even serious diseases and transforming mental health. [16]

4. Cold exposure for exercise recovery

Before you jump into the cold tub, it’s important to note that one of the times you shouldn’t practice cold exposure, is if you want to gain muscle size and strength directly following a hypertrophy or strength training session, as the inflammation following these types of workouts is largely beneficial. In other words, if you want to keep the gains after a strength workout, stay away from cold immersion for the four hours after your workout, or skip it that day. [17] Cold immersion has been shown to be highly beneficial following HIIT, cardio and endurance workouts however, and can be used as a form of active recovery. The cold exposure helps improve muscle recovery, reduces fatigue and post-workout soreness, and can aid in faster recovery. [18]. For best results following a HIIT or endurance workout, aim to hop straight into the ice bath or cold shower for 1 to 2 minutes. [19] If cold exposure can be helpful after some types of exercise, can cold immersion be beneficial before working out? As you already know, cold exposure encourages the release of adrenaline, noradrenaline and dopamine, all of which can boost energy levels and motivation, which are what you’ll want to have in high amounts before exercising. Ensure your cold immersion isn’t done too close to your workout, as you’ll need your muscles to be warm to exercise safely, but a cold shower or cold plunge in the morning before your workout can help get you motivated enough to work out with a better mind set and more energy.

What Is The Best Temperature For Cold Exposure?

Whilst many people choose cold immersion at temperatures below 15 degrees Celsius the important fact to note is that we’re all different, and everyone’s ability to handle cold will be different depending upon your background, current health state, cold tolerance, metabolism, and even the time of day. For women, cold tolerance can also differ greatly throughout various times of the menstrual cycle. To get the biggest benefits of cold exposure for you, you’ll need to choose a temperature that is uncomfortable and that you want to get out of, but that is also safe and tolerable. That’s what biohacking is all about – experimenting!

How Long To Do Cold Exposure For

Research shows a beneficial threshold of around 11 minutes of cold exposure in total per week. This can alter from person-to-person, and if you’ve been practicing cold immersion for a number of months or years, you may be able to handle longer amounts of time in the cold. Conversely, if you’re just starting cold exposure, you may total just a few minutes per week, which is absolutely fine too. Many studies are conducted on times ranging from 30 seconds, through to a minute, and up to two minutes. Generally, the lower the temperature, the less time you’re likely to spend in the water, and it’s important to ensure you’re always safe when practicing cold immersion. It’s wise to build up your cold tolerance gradually, so start with around 30 seconds, and build up to one to two minutes. To further enhance your cold exposure practice, you can then look to lower the temperature or increase your cold immersion time. [20]

What time of day is best for cold immersion?

Remembering that cold immersion is going to release stimulating hormones like adrenaline noradrenaline and dopamine into the body, it’s more beneficial to take a cold shower or ice bath in the earlier parts of the day. Almost ironically, your body temperature is also going to increase as you start to warm up after your shower, as the part of the brain known as the hypothalamus senses your body getting cold, and works to raise body temperature in order to maintain homeostasis. This is another reason for keeping your cold immersion to the morning or early afternoon, as the body’s circadian rhythms rely upon a drop in core body temperature in the evening in order to facilitate optimal sleep. By taking a cold shower at night, you could risk disrupting your sleep and decreasing recovery from your workouts and general day-to-day stresses.

Stacking your habits:

Cold immersion combined with fasting and coffee

Finally, in our blog on creating healthy habits that last, we covered how effective it is to stack your habits on top of each other to create a beneficial daily routine, to make sure you stick to your habits, and to get more benefit from your daily practices. It turns out that there are two tools in particular you can use to increase the motivation-boosting, energy-enhancing and fat-burning benefits of cold exposure, and they’re both pretty simple.

Fasted cold immersion

This method simply involves being in a fasted state when you take your cold shower, cold plunge, or cold walk in the morning. Being in a fasted state when waking or when intermittent fasting means levels of adrenaline, noradrenaline and dopamine, are already elevated, and so by placing your cold exposure on top of this, you’ll be further increasing these hormone levels.

Coffee and Cold Immersion

Research shows that drinking coffee (at the strength of roughly 2 to 3 shots) 60 to 100 minutes before cold exposure can increase the efficacy of dopamine receptors, [21] meaning the dopamine released via the cold shower can more efficiently bind to the receptors, and you’ll experience even greater benefits of the motivation, focus, and elevated mood associated with dopamine, as well as a significant boost to your motivation!

Biohacking is all about experimenting with the tools and practices that give you the best results. Remember to practice cold exposure safely, build up gradually, and play around with what works for you, depending upon your goals.

Sources

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  URL:http://feyz.kaums.ac.ir/article-1-4517-en.html